Perms and Coms question (1 Viewer)

[MichelleW]

Hi I need help with a question from the Cambridge 2u textbook (EX1C 13)
A piece of paper 0.01mm thick is folded successively 100 times. How thick is it now?

Most of the questions were alright but this one really stumped me.
Any help would be great.

 

[#RoadTo31Atar]

I think this is a geometric series question - you just need to put stuff into the formula

 

[mmmm.]

What is the answer?

 

[B1andB2]

usually with the folding qs you can just do 2^(how many folds) x thickness

= 2^100 x 0.01 in your case

are you sure you typed the q correctly? Because in the textbook it says 0.1 mm thickness lol

 

[#RoadTo31Atar]

arn^n-1

0.02x2^99

I think it's this because the first time you fold it it doubles so a is 0.02 instead of 0.01. I might wrong tho

 

[B1andB2]

arn^n-1

0.02x2^99

I think it's this because the first time you fold it it doubles so a is 0.02 instead of 0.01. I might wrong tho

do you have to use that weird formula?

because it yields the same answer as 2^100 x 0.01

 

[mmmm.]

PS: The question says 0.1mm not 0.01mm as OP said

 

[beetree1]

anyways any piece of paper cannot be folded more than 7times therefore the question is bull

 

[MichelleW]

usually with the folding qs you can just do 2^(how many folds) x thickness

= 2^100 x 0.01 in your case

are you sure you typed the q correctly? Because in the textbook it says 0.1 mm thickness lol

Yep my bad meant to type 0.1mm lol

 

[MichelleW]

Thanks for all the help I got it now

 

[CM_Tutor]

Hi I need help with a question from the Cambridge 2u textbook (EX1C 13)
A piece of paper 0.01mm thick is folded successively 100 times. How thick is it now?

Most of the questions were alright but this one really stumped me.
Any help would be great.

I'm tempted to say that the piece of paper's thickness has not changed. The stack of folded paper is much thicker than was the single, unfolded, sheet... but the single sheet remains the same thickness no matter how many times you fold it....